Cenospheres, which are lightweight, hollow spheres composed primarily of silica and alumina, do not typically have universally standardized grades like some other materials. However, their properties can vary based on their source and processing methods. It's important to note that the grading system for cenospheres can differ between manufacturers or suppliers. Therefore, it's advisable to refer to specific product specifications or consult with us to understand the quality and characteristics of the cenospheres being offered.